The present invention relates to fiber-optic communications networks, and more particularly, to semiconductor optical amplifiers used in such networks.
Fiber-optic networks are used to support voice and data communications. In optical networks that use wavelength division multiplexing, multiple wavelengths of light are used to support multiple communications channels on a single fiber.
Optical amplifiers are used in fiber-optic networks to amplify optical signals. For example, optical amplifiers may be used to amplify optical data signals that have been subject to attenuation over fiber-optic paths. A typical amplifier may include erbium-doped fiber coils that are pumped with diode lasers. Raman amplifiers and semiconductor optical amplifiers are also being investigated for use in fiber-optic links.
One problem with existing semiconductor optical amplifiers is that their maximum output powers tend to be lower than the maximum output powers available from other types of amplifiers.
It is an object of the present invention to provide semiconductor optical amplifiers for use in fiber-optic communications systems.
It is also an object of the present invention to provide semiconductor optical amplifiers that are capable of handling relatively high maximum output powers.
These and other objects of the invention are accomplished in accordance with the present invention by providing semiconductor optical amplifiers for use in optical amplifiers and other optical network equipment in fiber-optic communications networks. The fiber-optic networks may include communications links that are used to carry optical data signals associated with wavelength-division-multiplexing channels.
Semiconductor optical amplifiers may be provided that use multiple semiconductor optical amplifier devices. Isolators may be used between semiconductor devices to increase the overall power handling capacity of the semiconductor amplifiers.
Semiconductor optical amplifier devices may be provided that have increased power handling capabilities. These devices may use nonuniform drive current densities to enhance the output power capabilities of the devices without inducing lasing.
Further features of the invention and its nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the preferred embodiments.